@@ -2,6 +2,7 @@ 0.4.0: (Future)
 Features:
  - Officially supported ports for the Nintendo 3DS, Wii, and PlayStation Vita
  - I/O viewer
+ - Booting of multiboot images
 Bugfixes:
  - Qt: Windows no longer spawn in the top left on first launch
  - Qt: Fix install path of XDG desktop file with DESTDIR

@@ -183,7 +183,7 @@
 	ARMReset(context->cpu);
 
 	if (opts.skipBios) {
-		GBASkipBIOS(context->cpu);
+		GBASkipBIOS(context->gba);
 	}
 
 	struct GBACartridgeOverride override;

@@ -27,6 +27,9 @@
 static const size_t GBA_ROM_MAGIC_OFFSET = 3;
 static const uint8_t GBA_ROM_MAGIC[] = { 0xEA };
 
+static const size_t GBA_MB_MAGIC_OFFSET = 0xC3;
+static const uint8_t GBA_MB_MAGIC[] = { 0xEA };
+
 static void GBAInit(struct ARMCore* cpu, struct ARMComponent* component);
 static void GBAInterruptHandlerInit(struct ARMInterruptHandler* irqh);
 static void GBAProcessEvents(struct ARMCore* cpu);
@@ -181,9 +184,14 @@ gba->timersEnabled = 0;
 	memset(gba->timers, 0, sizeof(gba->timers));
 }
 
-void GBASkipBIOS(struct ARMCore* cpu) {
+void GBASkipBIOS(struct GBA* gba) {
+	struct ARMCore* cpu = gba->cpu;
 	if (cpu->gprs[ARM_PC] == BASE_RESET + WORD_SIZE_ARM) {
-		cpu->gprs[ARM_PC] = BASE_CART0;
+		if (gba->memory.rom) {
+			cpu->gprs[ARM_PC] = BASE_CART0;
+		} else {
+			cpu->gprs[ARM_PC] = BASE_WORKING_RAM;
+		}
 		int currentCycles = 0;
 		ARM_WRITE_PC;
 	}
@@ -398,6 +406,35 @@ ARMHotplugDetach(gba->cpu, GBA_COMPONENT_DEBUGGER);
 	gba->cpu->components[GBA_COMPONENT_DEBUGGER] = 0;
 }
 
+bool GBALoadMB(struct GBA* gba, struct VFile* vf, const char* fname) {
+	GBAUnloadROM(gba);
+	gba->romVf = vf;
+	gba->pristineRomSize = vf->size(vf);
+	vf->seek(vf, 0, SEEK_SET);
+	if (gba->pristineRomSize > SIZE_WORKING_RAM) {
+		gba->pristineRomSize = SIZE_WORKING_RAM;
+	}
+#ifdef _3DS
+	gba->pristineRom = 0;
+	if (gba->pristineRomSize <= romBufferSize) {
+		gba->pristineRom = romBuffer;
+		vf->read(vf, romBuffer, gba->pristineRomSize);
+	}
+#else
+	gba->pristineRom = vf->map(vf, gba->pristineRomSize, MAP_READ);
+#endif
+	if (!gba->pristineRom) {
+		GBALog(gba, GBA_LOG_WARN, "Couldn't map ROM");
+		return false;
+	}
+	gba->yankedRomSize = 0;
+	gba->activeFile = fname;
+	gba->memory.romSize = 0;
+	gba->memory.romMask = 0;
+	gba->romCrc32 = doCrc32(gba->pristineRom, gba->pristineRomSize);
+	return true;
+}
+
 bool GBALoadROM(struct GBA* gba, struct VFile* vf, struct VFile* sav, const char* fname) {
 	GBAUnloadROM(gba);
 	gba->romVf = vf;
@@ -675,7 +712,24 @@ uint8_t signature[sizeof(GBA_ROM_MAGIC)];
 	if (vf->read(vf, &signature, sizeof(signature)) != sizeof(signature)) {
 		return false;
 	}
+	if (GBAIsBIOS(vf)) {
+		return false;
+	}
 	return memcmp(signature, GBA_ROM_MAGIC, sizeof(signature)) == 0;
+}
+
+bool GBAIsMB(struct VFile* vf) {
+	if (!GBAIsROM(vf)) {
+		return false;
+	}
+	if (vf->seek(vf, GBA_MB_MAGIC_OFFSET, SEEK_SET) < 0) {
+		return false;
+	}
+	uint8_t signature[sizeof(GBA_MB_MAGIC)];
+	if (vf->read(vf, &signature, sizeof(signature)) != sizeof(signature)) {
+		return false;
+	}
+	return memcmp(signature, GBA_MB_MAGIC, sizeof(signature)) == 0;
 }
 
 bool GBAIsBIOS(struct VFile* vf) {
@@ -704,11 +758,15 @@ memcpy(out, &((struct GBACartridge*) gba->memory.rom)->id, 4);
 }
 
 void GBAGetGameTitle(struct GBA* gba, char* out) {
-	if (!gba->memory.rom) {
-		strncpy(out, "(BIOS)", 12);
+	if (gba->memory.rom) {
+		memcpy(out, &((struct GBACartridge*) gba->memory.rom)->title, 12);
 		return;
 	}
-	memcpy(out, &((struct GBACartridge*) gba->memory.rom)->title, 12);
+	if (gba->pristineRom) {
+		memcpy(out, &((struct GBACartridge*) gba->pristineRom)->title, 12);
+		return;
+	}
+	strncpy(out, "(BIOS)", 12);
 }
 
 void GBAHitStub(struct ARMCore* cpu, uint32_t opcode) {

@@ -149,7 +149,7 @@ void GBACreate(struct GBA* gba);
 void GBADestroy(struct GBA* gba);
 
 void GBAReset(struct ARMCore* cpu);
-void GBASkipBIOS(struct ARMCore* cpu);
+void GBASkipBIOS(struct GBA* gba);
 
 void GBATimerUpdateRegister(struct GBA* gba, int timer);
 void GBATimerWriteTMCNT_LO(struct GBA* gba, int timer, uint16_t value);
@@ -175,7 +175,10 @@ void GBAUnloadROM(struct GBA* gba);
 void GBALoadBIOS(struct GBA* gba, struct VFile* vf);
 void GBAApplyPatch(struct GBA* gba, struct Patch* patch);
 
+bool GBALoadMB(struct GBA* gba, struct VFile* vf, const char* fname);
+
 bool GBAIsROM(struct VFile* vf);
+bool GBAIsMB(struct VFile* vf);
 bool GBAIsBIOS(struct VFile* vf);
 void GBAGetGameCode(struct GBA* gba, char* out);
 void GBAGetGameTitle(struct GBA* gba, char* out);

@@ -3,49 +3,50 @@
 #include "gba/memory.h"
 
 const uint8_t hleBios[SIZE_BIOS] = {
-	0x06, 0x00, 0x00, 0xea, 0xfe, 0xff, 0xff, 0xea, 0x07, 0x00, 0x00, 0xea,
+	0x06, 0x00, 0x00, 0xea, 0xfe, 0xff, 0xff, 0xea, 0x0b, 0x00, 0x00, 0xea,
 	0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea, 0x00, 0x00, 0xa0, 0xe1,
-	0x28, 0x00, 0x00, 0xea, 0xfe, 0xff, 0xff, 0xea, 0x02, 0xf3, 0xa0, 0xe3,
-	0x00, 0x00, 0x00, 0x00, 0x00, 0xf0, 0x29, 0xe1, 0x00, 0x00, 0x5d, 0xe3,
-	0x01, 0xd3, 0xa0, 0x03, 0x20, 0xd0, 0x4d, 0x02, 0x00, 0x58, 0x2d, 0xe9,
-	0x02, 0xb0, 0x5e, 0xe5, 0x8c, 0xc0, 0xa0, 0xe3, 0x0b, 0xb1, 0x9c, 0xe7,
-	0x00, 0x00, 0x5b, 0xe3, 0x00, 0xc0, 0x4f, 0xe1, 0x00, 0x10, 0x2d, 0xe9,
-	0x80, 0xc0, 0x0c, 0xe2, 0x1f, 0xc0, 0x8c, 0xe3, 0x0c, 0xf0, 0x29, 0xe1,
-	0x00, 0x40, 0x2d, 0xe9, 0x0f, 0xe0, 0xa0, 0xe1, 0x1b, 0xff, 0x2f, 0x11,
-	0x00, 0x40, 0xbd, 0xe8, 0x93, 0xf0, 0x29, 0xe3, 0x00, 0x10, 0xbd, 0xe8,
-	0x0c, 0xf0, 0x69, 0xe1, 0x00, 0x58, 0xbd, 0xe8, 0x0e, 0xf0, 0xb0, 0xe1,
-	0x00, 0x00, 0x00, 0x00, 0x04, 0x20, 0xa0, 0xe3, 0x00, 0x00, 0x00, 0x00,
+	0x2c, 0x00, 0x00, 0xea, 0xfe, 0xff, 0xff, 0xea, 0x02, 0x03, 0xa0, 0xe3,
+	0x03, 0x10, 0xd0, 0xe5, 0xea, 0x00, 0x51, 0xe3, 0x02, 0x04, 0xa0, 0x13,
+	0x10, 0xff, 0x2f, 0xe1, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf0, 0x29, 0xe1,
+	0x00, 0x00, 0x5d, 0xe3, 0x01, 0xd3, 0xa0, 0x03, 0x20, 0xd0, 0x4d, 0x02,
+	0x00, 0x58, 0x2d, 0xe9, 0x02, 0xb0, 0x5e, 0xe5, 0x9c, 0xc0, 0xa0, 0xe3,
+	0x0b, 0xb1, 0x9c, 0xe7, 0x00, 0x00, 0x5b, 0xe3, 0x00, 0xc0, 0x4f, 0xe1,
+	0x00, 0x10, 0x2d, 0xe9, 0x80, 0xc0, 0x0c, 0xe2, 0x1f, 0xc0, 0x8c, 0xe3,
+	0x0c, 0xf0, 0x29, 0xe1, 0x00, 0x40, 0x2d, 0xe9, 0x0f, 0xe0, 0xa0, 0xe1,
+	0x1b, 0xff, 0x2f, 0x11, 0x00, 0x40, 0xbd, 0xe8, 0x93, 0xf0, 0x29, 0xe3,
+	0x00, 0x10, 0xbd, 0xe8, 0x0c, 0xf0, 0x69, 0xe1, 0x00, 0x58, 0xbd, 0xe8,
+	0x0e, 0xf0, 0xb0, 0xe1, 0x00, 0x00, 0x00, 0x00, 0x04, 0x20, 0xa0, 0xe3,
 	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-	0xe8, 0x00, 0x00, 0x00, 0xe0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0xf8, 0x00, 0x00, 0x00, 0xf0, 0x00, 0x00, 0x00,
 	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-	0x00, 0x00, 0x00, 0x00, 0x30, 0x01, 0x00, 0x00, 0xc0, 0x01, 0x00, 0x00,
-	0x0f, 0x50, 0x2d, 0xe9, 0x01, 0x03, 0xa0, 0xe3, 0x00, 0xe0, 0x8f, 0xe2,
-	0x04, 0xf0, 0x10, 0xe5, 0x0f, 0x50, 0xbd, 0xe8, 0x04, 0xf0, 0x5e, 0xe2,
-	0x00, 0x00, 0x00, 0x00, 0x02, 0xc0, 0x5e, 0xe5, 0x01, 0x00, 0xa0, 0xe3,
-	0x01, 0x10, 0xa0, 0xe3, 0x0c, 0x40, 0x2d, 0xe9, 0x01, 0xc3, 0xa0, 0xe3,
-	0x00, 0x00, 0x50, 0xe3, 0x00, 0x00, 0xa0, 0xe3, 0x01, 0x20, 0xa0, 0xe3,
-	0x03, 0x00, 0x00, 0x0a, 0xb8, 0x30, 0x5c, 0xe1, 0x01, 0x30, 0xc3, 0xe1,
-	0xb8, 0x30, 0x4c, 0xe1, 0x01, 0x03, 0xcc, 0xe5, 0x08, 0x02, 0xcc, 0xe5,
-	0xb8, 0x30, 0x5c, 0xe1, 0x01, 0x30, 0x13, 0xe0, 0x01, 0x30, 0x23, 0x10,
-	0xb8, 0x30, 0x4c, 0x11, 0x08, 0x22, 0xcc, 0xe5, 0xf7, 0xff, 0xff, 0x0a,
-	0x0c, 0x80, 0xbd, 0xe8, 0x00, 0x40, 0x2d, 0xe9, 0x02, 0x36, 0xa0, 0xe1,
-	0x01, 0x04, 0x12, 0xe3, 0x0f, 0x00, 0x00, 0x0a, 0x01, 0x03, 0x12, 0xe3,
-	0x05, 0x00, 0x00, 0x0a, 0x23, 0x35, 0x81, 0xe0, 0x04, 0x00, 0xb0, 0xe8,
-	0x03, 0x00, 0x51, 0xe1, 0x04, 0x00, 0xa1, 0xb8, 0xfc, 0xff, 0xff, 0xba,
-	0x16, 0x00, 0x00, 0xea, 0x01, 0x00, 0xc0, 0xe3, 0x01, 0x10, 0xc1, 0xe3,
-	0xa3, 0x35, 0x81, 0xe0, 0xb0, 0x20, 0xd0, 0xe1, 0x03, 0x00, 0x51, 0xe1,
-	0xb2, 0x20, 0xc1, 0xb0, 0xfc, 0xff, 0xff, 0xba, 0x0e, 0x00, 0x00, 0xea,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x01, 0x00, 0x00,
+	0xd0, 0x01, 0x00, 0x00, 0x0f, 0x50, 0x2d, 0xe9, 0x01, 0x03, 0xa0, 0xe3,
+	0x00, 0xe0, 0x8f, 0xe2, 0x04, 0xf0, 0x10, 0xe5, 0x0f, 0x50, 0xbd, 0xe8,
+	0x04, 0xf0, 0x5e, 0xe2, 0x00, 0x00, 0x00, 0x00, 0x02, 0xc0, 0x5e, 0xe5,
+	0x01, 0x00, 0xa0, 0xe3, 0x01, 0x10, 0xa0, 0xe3, 0x0c, 0x40, 0x2d, 0xe9,
+	0x01, 0xc3, 0xa0, 0xe3, 0x00, 0x00, 0x50, 0xe3, 0x00, 0x00, 0xa0, 0xe3,
+	0x01, 0x20, 0xa0, 0xe3, 0x03, 0x00, 0x00, 0x0a, 0xb8, 0x30, 0x5c, 0xe1,
+	0x01, 0x30, 0xc3, 0xe1, 0xb8, 0x30, 0x4c, 0xe1, 0x01, 0x03, 0xcc, 0xe5,
+	0x08, 0x02, 0xcc, 0xe5, 0xb8, 0x30, 0x5c, 0xe1, 0x01, 0x30, 0x13, 0xe0,
+	0x01, 0x30, 0x23, 0x10, 0xb8, 0x30, 0x4c, 0x11, 0x08, 0x22, 0xcc, 0xe5,
+	0xf7, 0xff, 0xff, 0x0a, 0x0c, 0x80, 0xbd, 0xe8, 0x00, 0x40, 0x2d, 0xe9,
+	0x02, 0x36, 0xa0, 0xe1, 0x01, 0x04, 0x12, 0xe3, 0x0f, 0x00, 0x00, 0x0a,
 	0x01, 0x03, 0x12, 0xe3, 0x05, 0x00, 0x00, 0x0a, 0x23, 0x35, 0x81, 0xe0,
-	0x03, 0x00, 0x51, 0xe1, 0x04, 0x00, 0xb0, 0xb8, 0x04, 0x00, 0xa1, 0xb8,
-	0xfb, 0xff, 0xff, 0xba, 0x06, 0x00, 0x00, 0xea, 0xa3, 0x35, 0x81, 0xe0,
-	0x01, 0x00, 0xc0, 0xe3, 0x01, 0x10, 0xc1, 0xe3, 0x03, 0x00, 0x51, 0xe1,
-	0xb2, 0x20, 0xd0, 0xb0, 0xb2, 0x20, 0xc1, 0xb0, 0xfb, 0xff, 0xff, 0xba,
-	0x00, 0x80, 0xbd, 0xe8, 0xf0, 0x47, 0x2d, 0xe9, 0x01, 0x04, 0x12, 0xe3,
-	0x02, 0x36, 0xa0, 0xe1, 0x23, 0x25, 0x81, 0xe0, 0x0b, 0x00, 0x00, 0x0a,
-	0x00, 0x30, 0x90, 0xe5, 0x03, 0x40, 0xa0, 0xe1, 0x03, 0x50, 0xa0, 0xe1,
-	0x03, 0x60, 0xa0, 0xe1, 0x03, 0x70, 0xa0, 0xe1, 0x03, 0x80, 0xa0, 0xe1,
-	0x03, 0x90, 0xa0, 0xe1, 0x03, 0xa0, 0xa0, 0xe1, 0x02, 0x00, 0x51, 0xe1,
-	0xf8, 0x07, 0xa1, 0xb8, 0xfc, 0xff, 0xff, 0xba, 0x03, 0x00, 0x00, 0xea,
-	0x02, 0x00, 0x51, 0xe1, 0xf8, 0x07, 0xb0, 0xb8, 0xf8, 0x07, 0xa1, 0xb8,
-	0xfb, 0xff, 0xff, 0xba, 0xf0, 0x87, 0xbd, 0xe8
+	0x04, 0x00, 0xb0, 0xe8, 0x03, 0x00, 0x51, 0xe1, 0x04, 0x00, 0xa1, 0xb8,
+	0xfc, 0xff, 0xff, 0xba, 0x16, 0x00, 0x00, 0xea, 0x01, 0x00, 0xc0, 0xe3,
+	0x01, 0x10, 0xc1, 0xe3, 0xa3, 0x35, 0x81, 0xe0, 0xb0, 0x20, 0xd0, 0xe1,
+	0x03, 0x00, 0x51, 0xe1, 0xb2, 0x20, 0xc1, 0xb0, 0xfc, 0xff, 0xff, 0xba,
+	0x0e, 0x00, 0x00, 0xea, 0x01, 0x03, 0x12, 0xe3, 0x05, 0x00, 0x00, 0x0a,
+	0x23, 0x35, 0x81, 0xe0, 0x03, 0x00, 0x51, 0xe1, 0x04, 0x00, 0xb0, 0xb8,
+	0x04, 0x00, 0xa1, 0xb8, 0xfb, 0xff, 0xff, 0xba, 0x06, 0x00, 0x00, 0xea,
+	0xa3, 0x35, 0x81, 0xe0, 0x01, 0x00, 0xc0, 0xe3, 0x01, 0x10, 0xc1, 0xe3,
+	0x03, 0x00, 0x51, 0xe1, 0xb2, 0x20, 0xd0, 0xb0, 0xb2, 0x20, 0xc1, 0xb0,
+	0xfb, 0xff, 0xff, 0xba, 0x00, 0x80, 0xbd, 0xe8, 0xf0, 0x47, 0x2d, 0xe9,
+	0x01, 0x04, 0x12, 0xe3, 0x02, 0x36, 0xa0, 0xe1, 0x23, 0x25, 0x81, 0xe0,
+	0x0b, 0x00, 0x00, 0x0a, 0x00, 0x30, 0x90, 0xe5, 0x03, 0x40, 0xa0, 0xe1,
+	0x03, 0x50, 0xa0, 0xe1, 0x03, 0x60, 0xa0, 0xe1, 0x03, 0x70, 0xa0, 0xe1,
+	0x03, 0x80, 0xa0, 0xe1, 0x03, 0x90, 0xa0, 0xe1, 0x03, 0xa0, 0xa0, 0xe1,
+	0x02, 0x00, 0x51, 0xe1, 0xf8, 0x07, 0xa1, 0xb8, 0xfc, 0xff, 0xff, 0xba,
+	0x03, 0x00, 0x00, 0xea, 0x02, 0x00, 0x51, 0xe1, 0xf8, 0x07, 0xb0, 0xb8,
+	0xf8, 0x07, 0xa1, 0xb8, 0xfb, 0xff, 0xff, 0xba, 0xf0, 0x87, 0xbd, 0xe8
 };

@@ -17,7 +17,11 @@ b irqBase
 b fiqBase
 
 resetBase:
-mov pc, #0x8000000
+mov r0, #0x8000000
+ldrb r1, [r0, #3]
+cmp r1, #0xEA
+movne r0, #0x2000000
+bx r0
 .word 0
 .word 0xE129F000
 

@@ -96,6 +96,10 @@ if (gba->memory.wram) {
 		mappedMemoryFree(gba->memory.wram, SIZE_WORKING_RAM);
 	}
 	gba->memory.wram = anonymousMemoryMap(SIZE_WORKING_RAM);
+	if (gba->pristineRom && !gba->memory.rom) {
+		// Multiboot
+		memcpy(gba->memory.wram, gba->pristineRom, gba->pristineRomSize);
+	}
 
 	if (gba->memory.iwram) {
 		mappedMemoryFree(gba->memory.iwram, SIZE_WORKING_IRAM);

@@ -167,10 +167,14 @@ GBAVideoAssociateRenderer(&gba.video, threadContext->renderer);
 	}
 
 	if (threadContext->rom) {
-		GBALoadROM(&gba, threadContext->rom, threadContext->save, threadContext->fname);
+		if (GBAIsMB(threadContext->rom)) {
+			GBALoadMB(&gba, threadContext->rom, threadContext->fname);
+		} else {
+			GBALoadROM(&gba, threadContext->rom, threadContext->save, threadContext->fname);
+		}
 
 		struct GBACartridgeOverride override;
-		const struct GBACartridge* cart = (const struct GBACartridge*) gba.memory.rom;
+		const struct GBACartridge* cart = (const struct GBACartridge*) gba.pristineRom;
 		memcpy(override.id, &cart->id, sizeof(override.id));
 		if (GBAOverrideFind(threadContext->overrides, &override)) {
 			GBAOverrideApply(&gba, &override);
@@ -225,8 +229,8 @@ movie->startPlaying(movie, false);
 		GBARRInitPlay(&gba);
 	}
 
-	if (threadContext->skipBios && gba.memory.rom) {
-		GBASkipBIOS(&cpu);
+	if (threadContext->skipBios && gba.pristineRom) {
+		GBASkipBIOS(&gba);
 	}
 
 	if (!threadContext->cheats) {
@@ -305,8 +309,8 @@ }
 		MutexUnlock(&threadContext->stateMutex);
 		if (resetScheduled) {
 			ARMReset(&cpu);
-			if (threadContext->skipBios && gba.memory.rom) {
-				GBASkipBIOS(&cpu);
+			if (threadContext->skipBios && gba.pristineRom) {
+				GBASkipBIOS(&gba);
 			}
 		}
 	}